Recall & Review
beginner
What does the NOT operator (~) do in embedded C?
The NOT operator (~) flips every bit of a number: 0 becomes 1, and 1 becomes 0. It's used to invert bits.
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beginner
How do you invert all bits of an 8-bit number 0b10101010 using NOT (~)?
Applying ~0b10101010 results in 0b01010101, flipping each bit from 1 to 0 or 0 to 1.
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intermediate
Why is NOT (~) useful in embedded programming?
It helps quickly toggle bits, create masks, or invert flags without loops, saving time and code space.
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intermediate
What happens if you apply NOT (~) to an unsigned int with value 0?
All bits become 1, so the result is the maximum unsigned int value (e.g., 0xFFFFFFFF for 32-bit).
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advanced
Can NOT (~) be used to invert only some bits of a number?
No, NOT (~) inverts all bits. To invert specific bits, combine NOT with masks and bitwise AND/OR.
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What does the ~ operator do in embedded C?
✗ Incorrect
The ~ operator flips every bit: 0 becomes 1, and 1 becomes 0.
If x = 0b00001111, what is ~x in 8-bit?
✗ Incorrect
NOT flips bits, so 00001111 becomes 11110000.
Can ~ operator invert only selected bits directly?
✗ Incorrect
~ always inverts all bits of the operand.
What is the result of ~0 for a 16-bit unsigned integer?
✗ Incorrect
~0 flips all zeros to ones, so all bits become 1 (0xFFFF).
Why might embedded programmers use ~ operator?
✗ Incorrect
~ operator is a fast way to flip bits directly.
Explain how the NOT (~) operator works to invert bits in embedded C.
Think about how each bit changes when you apply ~.
You got /4 concepts.
Describe a situation in embedded programming where using the NOT (~) operator is helpful.
Consider how flipping bits can simplify code.
You got /4 concepts.